Move UrlFetcher to content. I originally thought that it's only used by chrome code, but turns o...

chrome/common/net/url_fetcher.h

-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-// This file contains URLFetcher, a wrapper around net::URLRequest that handles
-// low-level details like thread safety, ref counting, and incremental buffer
-// reading.  This is useful for callers who simply want to get the data from a
-// URL and don't care about all the nitty-gritty details.
-//
-// NOTE(willchan): Only one "IO" thread is supported for URLFetcher.  This is a
-// temporary situation.  We will work on allowing support for multiple "io"
-// threads per process.
-
-#ifndef CHROME_COMMON_NET_URL_FETCHER_H_
-#define CHROME_COMMON_NET_URL_FETCHER_H_
-#pragma once
-
-#include <string>
-#include <vector>
-
-#include "base/memory/ref_counted.h"
-#include "base/message_loop.h"
-#include "base/platform_file.h"
-#include "base/time.h"
-
-class FilePath;
-class GURL;
-
-namespace base {
-class MessageLoopProxy;
-}  // namespace base
-
-namespace net {
-class HostPortPair;
-class HttpResponseHeaders;
-class URLRequestContextGetter;
-class URLRequestStatus;
-typedef std::vector<std::string> ResponseCookies;
-}  // namespace net
-
-// To use this class, create an instance with the desired URL and a pointer to
-// the object to be notified when the URL has been loaded:
-//   URLFetcher* fetcher = new URLFetcher("http://www.google.com",
-//                                        URLFetcher::GET, this);
-//
-// Then, optionally set properties on this object, like the request context or
-// extra headers:
-//   fetcher->SetExtraRequestHeaders("X-Foo: bar");
-//
-// Finally, start the request:
-//   fetcher->Start();
-//
-//
-// The object you supply as a delegate must inherit from URLFetcher::Delegate;
-// when the fetch is completed, OnURLFetchComplete() will be called with a
-// pointer to the URLFetcher.  From that point until the original URLFetcher
-// instance is destroyed, you may use accessor methods to see the result of
-// the fetch. You should copy these objects if you need them to live longer
-// than the URLFetcher instance. If the URLFetcher instance is destroyed
-// before the callback happens, the fetch will be canceled and no callback
-// will occur.
-//
-// You may create the URLFetcher instance on any thread; OnURLFetchComplete()
-// will be called back on the same thread you use to create the instance.
-//
-//
-// NOTE: By default URLFetcher requests are NOT intercepted, except when
-// interception is explicitly enabled in tests.
-
-class URLFetcher {
- public:
-  enum RequestType {
-    GET,
-    POST,
-    HEAD,
-  };
-
-  // Imposible http response code. Used to signal that no http response code
-  // was received.
-  static const int kInvalidHttpResponseCode;
-
-  class Delegate {
-   public:
-    // TODO(skerner): This will be removed in favor of the |source|-only
-    // version below. Leaving this for now to make the initial code review
-    // easy to read.
-    virtual void OnURLFetchComplete(const URLFetcher* source,
-                                    const GURL& url,
-                                    const net::URLRequestStatus& status,
-                                    int response_code,
-                                    const net::ResponseCookies& cookies,
-                                    const std::string& data);
-
-    // This will be called when the URL has been fetched, successfully or not.
-    // Use accessor methods on |source| to get the results.
-    virtual void OnURLFetchComplete(const URLFetcher* source);
-
-   protected:
-    virtual ~Delegate() {}
-  };
-
-  // URLFetcher::Create uses the currently registered Factory to create the
-  // URLFetcher. Factory is intended for testing.
-  class Factory {
-   public:
-    virtual URLFetcher* CreateURLFetcher(int id,
-                                         const GURL& url,
-                                         RequestType request_type,
-                                         Delegate* d) = 0;
-
-   protected:
-    virtual ~Factory() {}
-  };
-
-  // |url| is the URL to send the request to.
-  // |request_type| is the type of request to make.
-  // |d| the object that will receive the callback on fetch completion.
-  URLFetcher(const GURL& url, RequestType request_type, Delegate* d);
-
-  virtual ~URLFetcher();
-
-  // Sets the factory used by the static method Create to create a URLFetcher.
-  // URLFetcher does not take ownership of |factory|. A value of NULL results
-  // in a URLFetcher being created directly.
-#if defined(UNIT_TEST)
-  static void set_factory(Factory* factory) { factory_ = factory; }
-#endif
-
-  // Normally interception is disabled for URLFetcher, but you can use this
-  // to enable it for tests. Also see the set_factory method for another way
-  // of testing code that uses an URLFetcher.
-  static void enable_interception_for_tests(bool enabled) {
-    g_interception_enabled = enabled;
-  }
-
-  // Creates a URLFetcher, ownership returns to the caller. If there is no
-  // Factory (the default) this creates and returns a new URLFetcher. See the
-  // constructor for a description of the args. |id| may be used during testing
-  // to identify who is creating the URLFetcher.
-  static URLFetcher* Create(int id, const GURL& url, RequestType request_type,
-                            Delegate* d);
-
-  // Sets data only needed by POSTs.  All callers making POST requests should
-  // call this before the request is started.  |upload_content_type| is the MIME
-  // type of the content, while |upload_content| is the data to be sent (the
-  // Content-Length header value will be set to the length of this data).
-  void set_upload_data(const std::string& upload_content_type,
-                       const std::string& upload_content);
-
-  // Indicates that the POST data is sent via chunked transfer encoding.
-  // This may only be called before calling Start().
-  // Use AppendChunkToUpload() to give the data chunks after calling Start().
-  void set_chunked_upload(const std::string& upload_content_type);
-
-  // Adds the given bytes to a request's POST data transmitted using chunked
-  // transfer encoding.
-  // This method should be called ONLY after calling Start().
-  virtual void AppendChunkToUpload(const std::string& data, bool is_last_chunk);
-
-  // Set one or more load flags as defined in net/base/load_flags.h.  Must be
-  // called before the request is started.
-  void set_load_flags(int load_flags);
-
-  // Returns the current load flags.
-  int load_flags() const;
-
-  // The referrer URL for the request. Must be called before the request is
-  // started.
-  void set_referrer(const std::string& referrer);
-
-  // Set extra headers on the request.  Must be called before the request
-  // is started.
-  void set_extra_request_headers(const std::string& extra_request_headers);
-
-  // Set the net::URLRequestContext on the request.  Must be called before the
-  // request is started.
-  void set_request_context(
-      net::URLRequestContextGetter* request_context_getter);
-
-  // If |retry| is false, 5xx responses will be propagated to the observer,
-  // if it is true URLFetcher will automatically re-execute the request,
-  // after backoff_delay() elapses. URLFetcher has it set to true by default.
-  void set_automatically_retry_on_5xx(bool retry);
-
-  int max_retries() const { return max_retries_; }
-
-  void set_max_retries(int max_retries) { max_retries_ = max_retries; }
-
-  // Returns the back-off delay before the request will be retried,
-  // when a 5xx response was received.
-  base::TimeDelta backoff_delay() const { return backoff_delay_; }
-
-  // Sets the back-off delay, allowing to mock 5xx requests in unit-tests.
-#if defined(UNIT_TEST)
-  void set_backoff_delay(base::TimeDelta backoff_delay) {
-    backoff_delay_ = backoff_delay;
-  }
-#endif  // defined(UNIT_TEST)
-
-  // By default, the response is saved in a string. Call this method to save the
-  // response to a temporary file instead. Must be called before Start().
-  // |file_message_loop_proxy| will be used for all file operations.
-  void SaveResponseToTemporaryFile(
-      scoped_refptr<base::MessageLoopProxy> file_message_loop_proxy);
-
-  // Retrieve the response headers from the request.  Must only be called after
-  // the OnURLFetchComplete callback has run.
-  virtual net::HttpResponseHeaders* response_headers() const;
-
-  // Retrieve the remote socket address from the request.  Must only
-  // be called after the OnURLFetchComplete callback has run and if
-  // the request has not failed.
-  net::HostPortPair socket_address() const;
-
-  // Returns true if the request was delivered through a proxy.  Must only
-  // be called after the OnURLFetchComplete callback has run and the request
-  // has not failed.
-  bool was_fetched_via_proxy() const;
-
-  // Start the request.  After this is called, you may not change any other
-  // settings.
-  virtual void Start();
-
-  // Return the URL that this fetcher is processing.
-  virtual const GURL& url() const;
-
-  // The status of the URL fetch.
-  virtual const net::URLRequestStatus& status() const;
-
-  // The http response code received. Will return
-  // URLFetcher::kInvalidHttpResponseCode if an error prevented any response
-  // from being received.
-  virtual int response_code() const;
-
-  // Cookies recieved.
-  virtual const net::ResponseCookies& cookies() const;
-
-  // Return true if any file system operation failed.  If so, set |error_code|
-  // to the error code. File system errors are only possible if user called
-  // SaveResponseToTemporaryFile().
-  virtual bool FileErrorOccurred(base::PlatformFileError* out_error_code) const;
-
-  // Reports that the received content was malformed.
-  void ReceivedContentWasMalformed();
-
-  // Get the response as a string. Return false if the fetcher was not
-  // set to store the response as a string.
-  virtual bool GetResponseAsString(std::string* out_response_string) const;
-
-  // Get the path to the file containing the response body. Returns false
-  // if the response body was not saved to a file. If take_ownership is
-  // true, caller takes responsibility for the temp file, and it will not
-  // be removed once the URLFetcher is destroyed.
-  virtual bool GetResponseAsFilePath(bool take_ownership,
-                                     FilePath* out_response_path) const;
-
-  // Cancels all existing URLFetchers.  Will notify the URLFetcher::Delegates.
-  // Note that any new URLFetchers created while this is running will not be
-  // cancelled.  Typically, one would call this in the CleanUp() method of an IO
-  // thread, so that no new URLRequests would be able to start on the IO thread
-  // anyway.  This doesn't prevent new URLFetchers from trying to post to the IO
-  // thread though, even though the task won't ever run.
-  static void CancelAll();
-
- protected:
-  // How should the response be stored?
-  enum ResponseDestinationType {
-    STRING,  // Default: In a std::string
-    TEMP_FILE  // Write to a temp file
-  };
-
-  // Returns the delegate.
-  Delegate* delegate() const;
-
-  // Used by tests.
-  const std::string& upload_data() const;
-
-  // Return a reference to the string data fetched.  Response type must
-  // be STRING, or this will CHECK.  This method exists to support the
-  // old signiture to OnURLFetchComplete(), and will be removed as part
-  // of crbug.com/83592 .
-  const std::string& GetResponseStringRef() const;
-
-  void SetResponseDestinationForTesting(ResponseDestinationType);
-  ResponseDestinationType GetResponseDestinationForTesting() const;
-
- private:
-  friend class URLFetcherTest;
-  friend class TestURLFetcher;
-
-  // Only used by URLFetcherTest, returns the number of URLFetcher::Core objects
-  // actively running.
-  static int GetNumFetcherCores();
-
-  class Core;
-  scoped_refptr<Core> core_;
-
-  static Factory* factory_;
-
-  // If |automatically_retry_on_5xx_| is false, 5xx responses will be
-  // propagated to the observer, if it is true URLFetcher will automatically
-  // re-execute the request, after the back-off delay has expired.
-  // true by default.
-  bool automatically_retry_on_5xx_;
-  // Back-off time delay. 0 by default.
-  base::TimeDelta backoff_delay_;
-  // Maximum retries allowed.
-  int max_retries_;
-
-  static bool g_interception_enabled;
-
-  DISALLOW_COPY_AND_ASSIGN(URLFetcher);
-};
-
-#endif  // CHROME_COMMON_NET_URL_FETCHER_H_